The invention relates to card entry gates, and more particularly to card entry gates for vending machines and other automated systems capable of accepting authorized data-bearing cards in any lengthwise orientation while rejecting certain coins, unauthorized cards, and other foreign objects.
The importance of protecting card reading and writing devices against the insertion of foreign matter and improper cards has long been recognized. Because such machines are often left unsupervised, vandals may attempt to maliciously damage card slots or gain access to a machine by forcibly inserting foreign objects such as sticks, tools, and other items. And particularly in the case of non coin-operated vending machines, a customer may try to insert coins into the card slot, where the coins may become lodged. In addition, card processing devices, such as vending machines and automated teller machines, are often located outdoors and exposed to the elements. Thus, complicated internal mechanisms are relatively expensive, vulnerable, and may be subject to breakdown.
An additional problem is posed by the presence of jitter. Where an embossed card enters a narrow slot, the embossed portions of the card may rub and occasionally bind on portions of the slot, causing irregularities in the speed at which the card travels through the reader, known as "jitter." This makes it more difficult for a card reader to correctly resolve the data stored on the card. Furthermore, undesired wear on the embossed portions of the card may result.
Solutions to these problems have been proposed, but all have had significant shortcomings for a number of reasons. As indicated, machines incorporating a complicated card handling mechanism may be expensive and difficult to repair. In addition, because such machines may be widely located, the downtime suffered before a damaged machine is located and repaired may be significant, leading to customer dissatisfaction.
The configuration of data-bearing plastic cards of the type treated herein is now somewhat standardized by ISO specifications 7811-1 through 7811-5. Cards manufactured to conform with those specifications have a particular size, as well as a specified arrangement of a magnetic stripe and embossed portions. The card has a defined basic thickness, but the embossed portions are substantially thicker. When accepting a card into a card processing apparatus, it is important to protect not only the magnetic stripe (or perhaps other areas) from wear and abrasion, but as noted above, the thickened portions also should be protected from damage.
Prior card entry gates have used a variety of means to solve some of these problems. Some have required complex electromechanical systems to detect the presence of an authorized card before allowing the slot to open. See, for example, U.S. Pat. No. 3,909,595 to Morello et al., issued Sep. 30, 1975 and entitled "Entry Gate Construction for Credit Card Actuated Automatic Remote Banking Equipment." As indicated above, with such an elaborate mechanism, one must be concerned about the potential for significant additional cost, complexity, and unreliable operation of the entry gate. However, it is noteworthy that the system of Morello also includes a contoured card slot to reject foreign matter and allow the insertion of an embossed card having a magnetic stripe; however, it allows insertion of the card in only one orientation, and is unnecessarily complicated by the electromechanical components.
Other card entry gates have included complicated mechanical linkages to detect proper card size and thickness, among other qualities. See, for example, U.S. Pat. No. 4,171,737 to McLaughlin, issued Oct. 23, 1979 and entitled "Entry Control Device." Again, these systems prompt concern for possible fragility and expense in construction and upkeep. Such card slots may also require some amount of pressure to be exerted through a rigid card to operate the gate. See, for example, U.S. Pat. No. 3,995,728 to Kerby, issued Dec. 7, 1976 and entitled "Anti-Vandal Credit Card Gate." Because force must be applied through the card, these mechanical systems may not be easily adaptable to certain flexible plastic or paper cards, as in temporary cards, which would flex without opening the gate.
The shortcomings of prior card entry gates highlight the need for a simple, reliable device with no moving parts or electronic components which are subject to failure. Furthermore, the need exists for a device which will accept a variety of authorized cards in a range of varying thicknesses, in various orientations, without likely damage and without jitter.